A performance test tool shall be regarded as an intrinsic part of an IT product throughout its life-cycle.
In most cases performance requirements on an IT product will grew dramatically during its life-cycle. A consequence of this is that requirements on upscaling of performance test tools will follow.
Our solutions provide test tool scaling in three dimensions:
Simple scaling of a load generator by separation of logical and physical load
A common problem occurs when required load increases beyond a point where several load generator processes will have to run in parallel on separate hardware servers to create the demanded conditions on the tested system. Such situations increase the complexity in management of generated load and reporting of measurement results.
On MBC the complexity of running several physical load generator processes in parallel on separate hardware servers is hidden by a logical load generator.
Figure F-7: Logical and physical load generators
A logical load generator is a configuration entity that provides a simple and aggregated view to a test user when managing load levels and receiving measurement.
It handles all complexity of running multiple generator processes in parallel on separate hardware servers.
Automated distribution of simulated users across the load generator processes(Traffic Adapter processes).
Automated distribution of traffic frequencies (generated load) across the load generator processes (Traffic Adapter processes).
Automated collection of external performance metrics from the load generator processes (Traffic Adapter processes).
From the user's view it is one load generator sending service requests to a tested system and one load generator reporting response times, traffic frequences etc. no matter how complex the load generator setup is.
No manpower is therefore required to handle the increased complexity of running large capacity load generators.
Simple scaling of a performance test case
A configured Traffic Handler on MBC is a logical load generator representing one interface between MBC and the tested system.
Figure F-8: Traffic Set and Traffic Handlers
All Traffic handlers of a test case are configured in a Traffic Set that handles all interfaces between MBC and the tested system.
A test case in MBC has one or more Traffic handlers configured. Each configured Traffic Handler has its own mix of user scenarios, application scenarios, application protocols, transport protocols, and internet protocols.
A Traffic Set with multiple Traffic Handlers configured for different application protocols interfacing different components of a tested system enables MBC to scale to very complex workloads.
Simple scaling of physical resources
Scaling an MBC system for generating more load also requires more physical resources to carry out a larger task.
Figure F-9: MBC a scalable performance test system
An MBC system has two types of servers:
Monitor servers managing a performance test job.
Traffic servers carrying out the work of the configured Traffic Handlers.
Figure F-10: An MBC system with three Monitor servers and eight Traffic servers
In the figure above the MBC system has been expanded to three Monitor servers and eight Traffic servers. The Traffic servers can be shared between the Monitor servers in any configuration.
The effect on load capacity by adding one or more Traffic servers is linear, i.e. the capacity of each additional Traffic server is equal to each existing Traffic server as long as they have the same hardware configuration.